Stories that stick
Myths
All rainforests are tropical
There are two types of rainforests, tropical and temperate. Tropical rainforests are found closer to the equator where it is warm. Temperate rainforests are found near the cooler coastal areas further north or south of the equator. NASA Temperate rainforests filled with evergreen and laurel trees are lower and less dense than other kinds of rainforests because the climate is more equable, with a moderate temperature range and well-distributed annual rainfall. Britannica
The floor is an impassable jungle
Contrary to popular belief, the rainforest floor is not impassable. The ground surface is bare, except for a thin layer of humus and fallen leaves. Britannica The bottom layer or floor of the rainforest is covered with wet leaves and leaf litter. This material decomposes rapidly in the wet, warm conditions, sending nutrients back into the soil. Few plants are found on the floor of the forest due to the lack of sunlight. NASA
Rainforest soils are very fertile
Most rainforest soils tend to be permanently moist and soggy. They are not very fertile, because the hot, humid weather causes organic matter to decompose rapidly and to be quickly absorbed by tree roots and fungi. Britannica
It rains the same amount every month, or there is no dry season at all
Lying either side of the equator, tropical rainforest climates are characterised by high temperatures and year-round rainfall. Met Office Rainfall is over 60 mm of rain in every month, giving rise to thick rainforest and some of the highest densities of biodiversity seen on land. Met Office Though there are regional variations, June through September are generally the driest months, and December through March are the wettest. While it still rains a significant amount all year, precipitation often drops by half from the wettest months to the driest. NASA Rainforests may also be found in areas of the tropics in which a dry season occurs, such as the "dry rainforests" of northeastern Australia. In these regions annual rainfall is between 800 and 1,800 mm and as many as 75 percent of the trees are deciduous. Britannica Contrary to common thinking, not all tropical rainforests occur in places with high, constant rainfall; for example, in the so-called "dry rainforests" of northeastern Australia, the climate is punctuated by a dry season, which reduces the annual precipitation. Britannica
How much rain does a rainforest get?
These figures measure different things, so this site keeps them side by side. The Met Office characterises a tropical rainforest climate by year-round rainfall of over 60 mm in every month — a monthly minimum, not an annual total. Britannica says rainforests usually occur where annual rainfall is generally more than 1,800 mm (70 inches). NASA's rainforest biome page gives a typical year as 2,000 to 10,000 millimeters (79 to 394 inches). For the Amazon Basin, NASA JPL gives an annual average of 6 to 10 feet (1.8 to 3 meters), and a 2002 NASA Earth Observatory feature says more than 9 feet (2.7 meters) fall in portions of Amazonia. NASA's Manaus example, from 1970-2000, sums to 2,323 mm, with August as low as 68 mm — just over the Met Office's 60 mm monthly figure.
Every hot tropical landscape is a rainforest
Tropical regions also contain other climate zones, which are hot but have distinct dry seasons, unlike rainforests. Met Office Tropical savannah climates have a more pronounced dry season than monsoon areas. They also have grasslands, rather than rainforests. Met Office Tropical monsoon climates have a season of heavy rainfall, connected to a seasonal change in wind direction. Met Office Other kinds of rainforests include the monsoon forests, most like the popular image of jungles, with a marked dry season and a vegetation dominated by deciduous trees such as teak, thickets of bamboo, and a dense undergrowth. Britannica
It is settled that half the world’s species live in the Amazon
That is not something this site will state as settled. A 2002 NASA feature, still on the page we checked, says perhaps half. A 2024 Met Office article says ten per cent is thought to exist within the region. The full note is with the Amazon.